I'm new on Flutter, I'm still studying. I want to send email using my SMTP provider but I'm not able to. Can you help me??

Here my function:

import 'package:mailer/mailer.dart';
import 'package:mailer/smtp_server.dart';

void send_email(String strEmail) async {

  String smtpServerName = 'smtps.xxxxx.it';
   int smtpPort = 465;
   String smtpUserName = '[email protected]';
   String smtpPassword = 'mypassword';

  final smtpServer = SmtpServer(
    smtpServerName,
    port: smtpPort,
    ssl: true,
    ignoreBadCertificate: false,
    allowInsecure: false,
    username: smtpUserName,
    password: smtpPassword,
  );

  final message = Message()
    ..from = Address("[email protected]", "My App")
    ..recipients.add(strEmail)
    ..subject = 'Hello'
    ..html = 'Hi, how are you?';

  try {

    final sendReport = await send(message, smtpServer);
    print('Message sent: ' + sendReport.toString());
  } on MailerException catch (e) {
    print('Message not sent.');
    for (var p in e.problems) {
      print('Problem: ${p.code}: ${p.msg}');
    }
  }

   }

When I try to debug it , it doesn't work and it gives me those errors.

CHROME EMULATOR ERROR:

Error: Unsupported operation: RawSocket constructor
    at Object.throw_ [as throw] (http://localhost:52995/dart_sdk.js:5037:11)
    at Function.connect (http://localhost:52995/dart_sdk.js:55997:17)
    .......

ANDROID EMULATOR ERROR:

E/flutter (12712):  CERTIFICATE_VERIFY_FAILED: self signed certificate in certificate chain(handshake.cc:359))
E/flutter (12712): #0      _SecureFilterImpl._handshake (dart:io-patch/secure_socket_patch.dart:101:69)
E/flutter (12712): #1      _SecureFilterImpl.handshake (dart:io-patch/secure_socket_patch.dart:143:25)
E/flutter (12712): #2      _RawSecureSocket._secureHandshake (dart:io/secure_socket.dart:794:54)
E/flutter (12712): #3      _RawSecureSocket._tryFilter (dart:io/secure_socket.dart:924:19)
E/flutter (12712): <asynchronous suspension>